Hi Serge,
thx for your reply,
I have a Main.prg with function main and a main window win_1 and a second window win_2 (not main).
To keep the app more readable I decided to define any further window in separate prg-files outside the main.prg.
But I get this syntax-error, though the only change of the code in my initial post is, that I removed the semicolon and the main-statement.

I set windowtype to child. Do I have to set another windowtype?
When I come home from work I will send the source code.